I seem to be in a very nice, if confusing, situation. I have an offer for three books (Yay!) from one company, and a rather better offer but just for one book. Back to the agent...
My brother put it beautifully yesterday - not so much the white knuckle ride as the queueing for the ride. More waiting, so more time to get on with the sequel. But it's a great position to be in!
Here's my other dilemma. I've written two-and-a-half books with a supernatural theme, and have an offer on them. I have also written a crime novel. I had a lot of fun working on the characters at the time. No-one is all good or all bad. The victim, Caitlin, struggles with PTSD and her lowered credibility in the eyes of family and the law. The actual murderer whispered his diary into my imagination, creepy. He's fun to write, though. The man who was convicted of the attack (I think) is a great character. I had got to 60k before I realised I had based him on one of my brothers...not the above one. Whoops.
Now, if you are paid to write fantasy, will a publisher be interested in something from a different genre? Will they see it as time taken away from the writing they were initially interested in?